refactor(config): simplify config manager to single unified config

mini-nav/configs/config.yaml

@@ -0,0 +1,21 @@
+model:
+  name: "facebook/dinov2-large"
+  compression_dim: 256
+  pooling_type: "attention"  # attention-based Top-K
+  top_k_ratio: 0.5           # Keep 50% of tokens
+  hidden_ratio: 2.0          # MLP hidden = compression_dim * 2
+  dropout_rate: 0.1
+  use_residual: true
+  device: "auto"             # auto-detect GPU
+
+visualization:
+  plot_theme: "plotly_white"
+  color_scale: "viridis"
+  point_size: 8
+  fig_width: 900
+  fig_height: 600
+
+output:
+  directory: "./outputs"
+  html_self_contained: true
+  png_scale: 2               # 2x resolution for PNG